(a) Field of the Invention
This invention relates to 8-chlorodibenz[b,f][1,4]-oxazepine-10(11H)-carboxylic acid, 2-(alkoxy-containing acyl)hydrazides that are useful pharmacological agents. These compounds are prostaglandin antagonists having analgesic activity.
Analgesics are agents used in the treatment of pain and often are useful in alleviating inflammation. The major classes of analgesics include narcotic analgesics (or opiates) and analgesic-antipyretics such as the salicylates. Although the efficacy of opiates in relieving pain is well-established, the associated addiction liability is a distinct disadvantage. Although salicylate and salicylate-like agents (non-steroidal antiinflammatory agents) are also efficacious in relieving pain, they often exhibit undesirable side effects such as gastrointestinal irritation (as with aspirin), allergic response (as with aspirin), or liver toxicity with extended use (as with acetaminophen). The compounds included in this invention are neither opiates nor salicylates and may be expected not to exhibit the disadvantages of either class of compound.
(b) Prior Art
The closest prior art discloses compounds of the following formula wherein group B is carbonyl (CO) or sulfonyl (SO.sub.2) and wherein A may be alkyl or substituted alkyl. The prior art does not, however, disclose the alkoxyalkyl or (alkoxy)alkoxyalkyl compounds of this invention. ##STR1##
More specifically, U.S. Pat. No. 3,534,019 discloses compounds in which B and A together constitute "lower alkanoyl," and U.S. Pat. No. 3,989,719 discloses compounds in which B and A together constitute "higher alkanoyl." Thus, U.S. Pat. Nos. '019 and '719 each disclose compounds in which A is a hydrocarbon. The alkoxyalkyl or (alkoxy)alkoxyalkyl compounds of this invention are not disclosed.
U.S. Pat. Nos. 4,045,442, 4,125,532 (division of '442), and 4,170,593 (division of '532) disclose compounds in which B is carbonyl and A is (substituted amino)alkyl. The alkoxyalkyl or (alkoxy)alkoxyalkyl compounds of this invention are not disclosed.
U.S. Pat. Nos. 3,917,649 and 3,992,375 (division of '649) disclose compounds in which B is carbonyl or sulfonyl: where B is sulfonyl, A may be alkyl, haloalkyl, aryl, or aralkyl; and where B is carbonyl, A may be haloalkyl, alkenyl, or aryloxyalkyl. However, U.S. Pat. Nos. '649 and '375 do not disclose corresponding compounds in which A is alkoxyalkyl or (alkoxy)alkoxyalkyl. With respect to disclosure of the aryloxyalkyl compound, one skilled in the art will understand that steric, chemical, and other properties of aromatic ethers are distinguishable from those of alkyl ethers. Thus, the compounds of this invention are structurally distinct from the prior art.